| Summary: | Using first principles molecular calculations, based on the Density Functional Theory (DFT), structural and electronic properties of hybrid graphene—like silicon—germanium circular nanosheets of hexagonal symmetry are investigated. The exchange—correlation functional of Perdew—Wang (PW) in the local spin density approximation (LSDA) based on the pseudopotentials of Dolg—Bergnre is applied. The finite extension nanosheets are represented by the CnHm—like cluster model with mono—hydrogenated armchair edges. Changes of the physicochemical properties were analyzed to learn on the chemical composition. We have obtained that the corrugation of the hybrid nanosheets is maintained (with respect to the pristine nanosheets of Ge and Si) and is more pronounced when there is a high percentage of germanium. Moreover, hybrid nanosheets have ionic bonds (polarity in the interval from 0.18 to 0.77 D) and exhibit a semimetal behavior. Three types of chemical compositions are considered: 1) the one—one relationship, 2) formation of Ge dimers and 3) formation of Ge hexagons. In each case it is observed an increase in the chemical reactivity. Finally, analyzing the work function we conclude that in cases 1) and 2) the chemical compositions improve the efficiency of the field emission and thereby they could expand the scope of nanotechnology applications.
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